// let a = 1;
// a = 'e'; // 将 js 变成 静态的；变量类型不再能改变；

let a:number = 1;
let b = 2;

const getUserInfos = (user:{name:string,age:number}) => {
    console.log(user);
    return `name:${user.name} age:${user.age}`;
}

getUserInfos({name:'liuyu',age:14});

